Use of Kaolin Clay in Aqueous Barrier Coating Applications, 23TAPPICon

More sustainable barrier coatings based on latex or biopolymer based aqueous dispersion barrier coatings are clearly emerging as interesting alternatives to the traditional extruded or surface active barrier materials. In this work, studies were performed to determine the influence of different kaolin clays in latex binder based aqueous coatings on barrier properties, namely, oil and grease, water resistance, and water vapor transmission rate by applying coatings to solid bleached sulfate (SBS) paperboard substrate in the laboratory. Five different ultrafine, delaminated, and undelaminated clays with different particle size distributions and shape factors were included. The aim was to explore potential benefits of using kaolin clay to replace some of the latex binder in coating and improve or maintain various types of barrier performance and blocking without negatively influencing the other performance attributes including heat seal. The results obtained were found to be highly dependent on coat weight and binder type. The delaminated clay with the highest shape factor provided better barrier properties than the clays of low shape factor as anticipated. The ultrafine and undelaminated clays required significantly higher coat weights to reach satisfactory barrier properties. Coatings with different latex levels indicated that a considerably high proportion of coarse clay can be incorporated to replace latex binder, and still achieve exceptional barrier properties. Furthermore, a change in binder system was found to significantly alter the barrier properties and the role that a mineral pigment can play. The results indicate that a proper selection of binder systems for each barrier property would be required while considering the clay/latex coating systems.

TAPPI conference proceedings and presentations, technical papers, and publication articles provide technical and management data and solutions on topics covering the Pulp, Paper, Tissue, Corrugated Packaging, Flexible Packaging, Nanotechnology and Converting Industries.

Simply select the quantity, add to your cart and your conference paper, presentation or article will be available for immediate download.